In a particular application, the product is of the gel or cream type, for example for a use in cosmetics or for pharmaceutical treatments.
Systems for dispensing are known comprising a pump provided with a feed tube for the product under pressure whereon a push-button is fixed to actuate the displacement of said tube on a dispensing/suction stroke of the product.
In particular, the push-button can include an actuator body having an orifice for ejecting the product and a sleeve having a mounting well of said push-button on the feed tube of the pump. As such, by pressing on the body of the push-button, the pump is actuated to dispense the product in the form of a small amount or a continuous stream.
The systems for dispensing can be provided with a means for reversible closing of the orifice for ejecting the product between two dispensings, in order to limit the contacts between the outside air and the product remaining in the pump, in particular in order to avoid a drying and/or a degradation of said product over time.
To do this, the use of an elastically deformable sleeve is known whereon is formed a lip which can be displaced by application of the dispensing pressure on it. The reversible closing can then be obtained by arranging the sleeve on the body, with said lip in sealed contact in the orifice for ejecting the product, the displacement of said lip opening said orifice.
However, the sleeves which are components moulded separately then added on the body, have the disadvantage of a low mechanical resistance, i.e. they are sometimes carried away by the product stream. In addition, during industrial production at high rates, they are difficult to position on the body, as they are constituted of a flexible material and therefore often adherent to the walls of the feed chutes and the members for grasping of the assembly machines.
According to another known embodiment, the reversible closing can be obtained by means of a closing off valving element of the ejection orifice, said valving element able to be displaced between its closing off and ejection positions on the actuating stroke of the push-button, in particular at the beginning of this stroke.
However, the carrying out of the closing off valving elements is often complex, the components are difficult to produce and their assembly is not easy, which increases the costs of industrial production.
The invention aims to simplify the carrying out of dispensing systems provided with a closing off valving element of the ejection orifice by proposing a design comprised of parts that are simple to carry out and in a limited number.
Furthermore, the invention proposes a seal of the closing which is improved in such a way as to be able to dispense products of which the sensitivity to air is substantial. Consequently, the combined use of a dispensing system according to the invention with a bottle containing an air-sensitive product is particularly advantageous.
In particular, by sensitivity to air, products are provided containing a solvent that is able to evaporate rapidly, for example with an alcohol or water base, or containing photosensitive substances, for example solar filters, or easily oxidizable, for example vitamins in particular vitamin C.
Moreover, the operation of the dispensing system according to the invention limits the pressurisation of the product during the dispensing. As such, the combined use of a dispensing system according to the invention with a bottle containing a product sensitive to mechanical stresses is also particularly advantageous.
In particular, by sensitivity to mechanical stresses, products are provided, for example creams, able to undergo a physical-chemical transformation under pressure, in particular a separation or a phase change.
The operation of the dispensing system according to the invention also makes possible the dispensing of particularly viscous products.